1. Field of the Invention
This invention relates to a device for joining together tubular members. More specifically, this invention relates to a device for joining tubular bed frame members.
2. Information Disclosure Statement
In previous techniques to joint tubular members, two parallel tubes are joined by a transverse tube. A rod is centered in the transverse tube by a washer disposed at each end of the transverse tube. A slot is provided at one end or at both ends of the rod. The slotted ends of the rod penetrate into the parallel tubes and a wedge is forced in each slot of the rod. In thin wall tubes, the rigidity of the joint is in direct proportion to the bearing surface between the wedge and the inner surface of the parallel tubes and it is in inverse proportion to the area of the hole of the parallel tube through which the rod penetrates. In order to use holes of small area in the parallel tubes and at the same time accomplish large bearing surface between the wedge and the inner surface of the parallel tube, a washer is interposed between the wedge and the inner surface of the parallel tube. It is obvious that placing the washer over the rod is not an easy task when the rod is at a relatively long distance from the end of the parallel tube. Furthermore, after the washer is in place, the insertion of the wedge in the slot becomes more difficult because the wedge cannot slide on the inner surface of the parallel tube.
U.S. Pat. No. 911,863 to Adams discloses a metal bed frame in which a plug disposed within a transverse tube includes a spigot which extends through a hole in one of the parallel tubes. The spigot defines a slot for the reception of a wedge.
U.S. Pat. No. 1,061,487 to Moore, teaches a one-piece rod which extends through a hole in one of the parallel tubes. The rod defines a slot which is disposed radially to the center of the parallel tube. The transverse tube is locked to the parallel tube by means of a wedge which cooperates with the slot.
Although the prior art devices provide a joint having a smooth external surface, they suffer from a certain lack of rigidity because the bearing surface of the wedge relative to the internal surface of the parallel tube or alternatively, an intervening bearing washer was relatively small. It is the primary object of the present invention to provide a device for joining tubular members that overcomes the aforementioned inadequacies of the prior art devices and provides an improvement which significantly contributes to the rigidity and ease of assembly of cooperating tubular members.
Another object of the present invention is the provision of a wedge which defines a longitudinal slot, the slot cooperating with a rod which extends through a transverse tube and through a hole defined by a second tube angularly disposed relative to the transverse tube.
Another object of the present invention is the provision of a device for joining angularly disposed tubes which is both economical to produce and easy to assemble.
The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed to be merely illustrative of some of the more pertinent features and applications of the invention. Many other beneficial results can be attained by applying the disclosure of the invention in a different manner or modifying the invention within the scope of the disclosure. Particularly with regard to the use of the invention disclosed herein, this should not be construed as limited to joining tubular bed frame members, but should include a device for joining together any angularly disposed tubular members.